Convert vanilla CSS with a custom at-rule for element queries into either Caffeinated Style Sheets (using @supports) that can be read client-side in the browser to control JS plugins, or output JavaScript output that calls the plugins directly. Run with Deno: deno preprocess-element-queries.js input-css.css css

Paste this rule in your browser's JS console on a loaded web page to log all rules targeting <option> tags. Change the text 'option' in the regex on line 7 to something else to filter for a different tag